Mandatory testing for COVID- 19 will start from March 1, 2021. The company can test either by a healthcare professional, or by the so-called self-tests (where employees test themselves).
You can use the services of health professionals, which can be, for example, an occupational physician, or existing test sites, you will learn more in a life situation Business activity> Mandatory Comprehensive Testing of Employees.
Mandatory testing of public office employees is very similar. For more info Offices and Institutions>Mandatory Covid-19 testing of public office staff.
Mandatory testing of school employees and school facilities employees can be found in Education>Mandatory testing of school employees.